# Attosecond helical pulses

## TL;DR

This paper presents an analytical model for attosecond pulses with spatiotemporal helical structures generated by nonlinear optical processes, enabling better understanding and potential applications of these complex light fields.

## Contribution

It provides a simple analytical solution describing helical attosecond pulses, facilitating their study and application, especially in matter interaction.

## Key findings

- Analytical model for helical attosecond pulses
- Helical pulses can beat the minimum duration limit of vortex pulses
- Topological charge dispersion influences pulse duration

## Abstract

We find a solution of the wave equation in the paraxial approximation that describes the attosecond pulses with spatiotemporal helical structure in the phase and in the intensity recently generated by means of highly nonlinear optical processes driven by visible or infrared femtosecond vortex pulses. Having a simple analytical model for these helical pulses will greatly facilitate the study of their predicted applications, particularly their interaction with matter after their generation. It also follows from our analysis that the topological charge dispersion inherent to helical pulses allows to beat the minimum duration to which a pulsed vortex without charge dispersion is limited.